Metabolic effects of marijuana smoking and the administration of synthetic cannabinoids in human volunteers and experimental animals are investigated. Urine and blood samples of subjects fed with controlled diet are collected before and after marijuana administration, and subsequently analyzed. High-resolution glass capillary columns are used to record metabolic profiles of volatile constituents of these body fluids, steroids, and urinary acids. Differences in profiles of normal body constituents due to marijuana administration are studied. Gas chromatography-mass spectrometry is used to identify affected metabolites and thus provide clues for further studies at the cellular level. Similar experimental techniques will be employed for acute and chronic toxicological studies in rats under controlled conditions.